Banca de DEFESA: FELIPE SERGIO BASTOS JORGE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : FELIPE SERGIO BASTOS JORGE
DATA : 16/02/2018
HORA: 09:00
LOCAL: Centro Federal de Educação Tecnológica de Minas Gerais
TÍTULO:

Influência da cinza de casca de arroz na interface entre a matriz cimentícia e o reforço com fibras de aço.

PALAVRAS-CHAVES:

Adhesion, RHA, Steel fiber, ITZ.

PÁGINAS: 80
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
SUBÁREA: Estruturas
RESUMO:

Concrete has high compressive strength and durability, but its ductility is low, which makes it a brittle material with little capacity for energy absorption, or toughness. In this sense, research with fibers incorporated in concrete has been directed with the objective of adding toughness. In cement-based composites, the interfacial transition zone (ITZ) is one in which the first cracks arise which, when propagated, lead to a material failure. The performance of fiber reinforced cement-based composites depends on stress transfer process efficiency to fibrous reinforcement, in order to guarantee the assembly operation. Among the determinants of this efficiency is the quality of cementitious matrix that is given by its density, that is, as interface between materials becomes dense, the adhesion between these components increases. Mineral additions have been incorporated into cement matrixes with two fundamental objectives: to give a sustainable destination to agroindustrial waste and to improve cement-based composites properties. Rice husk ash (RHA), which is produced by burning rice hulls for energy generation purposes, has a high content of amorphous silica, which gives it high potential for its pozzolanic activity. The objective of this research was to evaluate the effects of the incorporation of steel fibers and RHA in concretes whose formulation is used in railway lines production. For this, characterization tests of fresh and hardened concrete currently used in production were carried out, four-point flexural tests on the fiber-reinforced concretes in the percentages of 0.5, 0.75 and 1.0% with and without RHA and single fiber pullout tests in propositions with and without RHA. The results showed gains in load peaks, residual resistance post-cracking and toughness. Use of RHA proved to be effective and is a good alternative for increasing the properties of reinforced concrete with steel fibers.

 

MEMBROS DA BANCA:
Presidente - CONRADO DE SOUZA RODRIGUES
Externo à Instituição - FLAVIO DE ANDRADE SILVA - PUC - RJ
Interno - PAULO HENRIQUE RIBEIRO BORGES